Eating Disorders, Nutrition, and Obesity
Eating disorders
Anorexia nervosa involves restriction, fear of weight gain, and body image disturbance; atypical anorexia occurs at normal weight. Bulimia nervosa involves binge-purge behavior; binge-eating disorder involves binges without purging; ARFID involves avoidance without body image concerns. Medical instability includes bradycardia, hypotension, orthostasis, hypothermia, dehydration, and electrolyte abnormalities. Weight is not the only marker. Refeeding syndrome, especially hypophosphatemia, can occur with rapid reintroduction of calories.
Obesity and nutrition
Screen with BMI percentile. Assess comorbidities such as hypertension, dyslipidemia, prediabetes, fatty liver, and sleep apnea. Treatment is family-based lifestyle support; pharmacotherapy and bariatric surgery have roles for severe adolescent obesity. Avoid stigmatizing language.
Traps
Do not exclude an eating disorder because weight is normal. Do not miss dental erosion or laxative abuse in bulimia. Do not focus only on weight in atypical anorexia. Do not refeed aggressively without monitoring.
Worked example
A 15-year-old has lost 10% body weight, heart rate 48, and orthostatic dizziness. This suggests medical instability; arrange urgent medical stabilization and eating disorder evaluation rather than outpatient diet advice alone.